//天空盒的顶点着色器，假定了顶点的数据为：
//位置

cbuffer SceneData : register( b7 )
{
	matrix View;
	matrix Projection;
	float4 lightDir;
	float4 eyePosition;
}

//顶点着色器输出
struct VS_OUTPUT
{
    float4 Pos : SV_POSITION;
	float3 WorldPosition : TEXCOORD1;
};

VS_OUTPUT Main( float4 Pos : POSITION) 
{
	VS_OUTPUT output = (VS_OUTPUT)0;
	output.Pos = Pos;
	output.Pos = mul( output.Pos, View );
	output.Pos = mul( output.Pos, Projection );
	output.WorldPosition = Pos;
    return output;
}